Greenhouse Ventilation Gearbox - Self-Braking - Manual Crank Winder for Polytunnel Roll-Up Curtains

Greenhouse Roll-Up Side Gearbox - Manual Crank for Polytunnel Ventilation

Our Greenhouse Roll-Up Side Gearbox is the core component for providing effortless manual control over your side wall curtains. This robust mechanical winder allows you to precisely manage airflow, regulate temperature, and maintain the perfect growing environment through the warmer months.

Best For Commercial growers, nursery operators, and greenhouse builders needing a robust and reliable mechanical winder for constructing or repairing manual roll-up side ventilation systems on polytunnels and greenhouses.

Key Features

• ✔ Effortless Operation: The internal gearing provides a significant mechanical advantage, making it easy to raise and lower long and heavy side curtains with minimal effort using a crank handle (sold separately).

• ✔ Precise Temperature & Airflow Control: Allows you to make fine adjustments to your side wall opening, giving you precise control over ventilation to manage heat and humidity, which is critical as we head into summer.

• ✔ Self-Braking for Security: Features an integrated self-braking mechanism that automatically locks the curtain in any position. This prevents the curtain from unravelling in high winds and ensures it stays exactly where you set it.

   

• ✔ Heavy-Duty Construction: Built with a durable, weather-resistant housing and robust internal gears, this gearbox is designed to provide years of reliable, maintenance-free service in a demanding greenhouse environment.

How It Works This gearbox is the engine of your manual roll-up system. It is designed to move along a drive shaft (climbing bar). When operated with a crank handle, its internal gears drive the unit up or down the length of your greenhouse, winding the curtain material around a roller bar. This action smoothly and evenly opens or closes the side wall for ventilation.

Specifications

• Product: Manual Greenhouse Gearbox / Winder

• Application: Roll-Up Side Wall Curtains

• Mechanism: Self-Braking Crank Winch

• Housing: Weather-Resistant Casing

Ideal For (Uses)

• Manually opening and closing long roll-up side walls on single-span and multispan greenhouses.

• Precisely controlling ventilation to reduce heat build-up on hot spring and summer days.

• Retrofitting existing polytunnels with a reliable and easy-to-use manual ventilation system.

• Repairing or upgrading old, broken, or inefficient side wall winding mechanisms.